Of particular worry is accelerated methane release from peat bogs in the thawing permafrost, creating a positive feedback loop (with potentially irreversible consequences) [1] [2].
We’re rapidly running out of runway to mitigate the worst of climate change.
I dread to think how many joules of energy it’s going to take for us to stop emitting carbon, but also sequester that released since the Industrial Age began. I suppose there is some consolation in that enough sunlight hits the Earth in an hour to power humanity for a year, so the clean energy is there for the taking. It’s just going to take decades of sunlight to step back down the carbon curve [3]. Such is the cost of burning ancient sunlight.
[1]https://en.wikipedia.org/wiki/Arctic_methane_emissions